A new indole alkaloid (1), together with eight known indole alkaloid derivatives (2–9), was isolated from Hosta plantaginea for the first time. The structures of compounds 1–9 were elucidated on the basis of comprehensive spectroscopic analyses and references. Compounds 1–9 were evaluated for their inhibition of steroid 5α-reductase activity in vitro. Among them, compounds 1 and 2 showed important inhibition of steroid 5α-reductase activities.

中文翻译：

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玉簪中的吲哚生物碱和体外类固醇 5α-还原酶活性的抑制

首次从车前草中分离出一种新的吲哚生物碱 (1) 以及八种已知的吲哚生物碱衍生物 (2-9)。在综合光谱分析和参考文献的基础上阐明了化合物 1-9 的结构。评估了化合物 1-9 对体外类固醇 5α-还原酶活性的抑制作用。其中，化合物1和2显示出对类固醇5α-还原酶活性的重要抑制作用。